1) Field of the Invention
The present invention relates to a moving picture coding control apparatus executes an optimum control of coding parameters within a given range of data quantity, and a coding control database generating apparatus for use in portable devices.
2) Description of the Related Art
In a moving picture coding system like moving pictures experts group (MPEG), it is essential to perform an optimum control of coding parameters. Such control is performed to provide users with a high-quality picture reproduction service with a small quantity of moving picture data, or in order to obtain a high-quality picture in a portable moving-picture reproduction terminal that has a limited data storage capacity.
In the conventional technique, various kinds of coding parameters have been controlled for data allocation, based on only local information on coding blocks. Therefore, according to the conventional technique, when there is a small data quantity for allocation to whole blocks, it has not been possible to set optimum local coding parameters for realizing a data allocation to each block in good balance within frames or between frames. Consequently, this has been a cause of distortion in various kinds of images.
For example, while an excessive data quantity is allocated to a certain coding block, a sufficient data quantity cannot be allocated to blocks that require allocation of a sufficient data quantity such as a boundary area. This imbalance has caused the occurrence of block noise or mosquito noise. Further, according to the conventional technique, the setting of coding parameters that takes into account the continuity between adjacent blocks has not been carried out. Therefore, this has caused the occurrence of block noise. Further, when a scene changes between frames, data has not been suitably allocated to take balance in data quantity between the frames. Therefore, this has also caused the occurrence of a phenomenon that a reproduced moving picture has an unnatural movement.